Manila  - The Philippines' troubled southern region of Mindanao could see an escalation of hostilities if Malaysian peacekeepers pull out from monitoring a ceasefire there between the government and Muslim separatist rebels, a Filipino official warned Tuesday.

"The stable and peaceful condition we're having now in Mindanao would not be very sure if the Malaysians [leave the area]," government negotiator Rodolfo Garcia, said when asked about Kuala Lumpur's plan to withdraw once the mandate of the current mission expires in September.

A Malaysian peacekeeping force has been in Mindanao since 2004, leading an international monitoring team to ensure the compliance of the Philippine military and the Moro Islamic Liberation Front (MILF) with a ceasefire forged in 2001.

Other members of the team are from Brunei, Libya, Canada and Japan.

The deployment of the team has greatly decreased violence between the Philippine military and the MILF, which is the largest Muslim rebel group fighting for a separate Islamic state in Mindanao, home of the country's Muslim minority.

Garcia, the chief government peace negotiator with the MILF, said the planned pullout of the Malaysian contingent could have a negative impact on the implementation of the ceasefire and the peace negotiations.

According to reports from Kuala Lumpur, Malaysian Foreign Minister Rais Yatim said the decision was based on the fact that the peace talks have not been progressing.

"The thing is, we have to get cooperation from both sides," he told Malaysia's official Bernama news agency, "but if one party is not making the effort, we will have to end the mission."

Garcia admitted that progress in the negotiations has been slow as the government reviews its proposals to the MILF for the creation of a Muslim homeland in Mindanao, which would technically enlarge an existing autonomous Muslim region.

"I think it is the government's right to conduct due diligence on what my panel might recommend or propose to the cabinet, to the president," he said, "so I would wait for a little time for this review of the proposals."

Garcia said he was still hopeful that an agreement would be signed by August.

Peace talks between the Philippine government and the MILF have been suspended since September 2006 over disagreements on how to set up the proposed Islamic homeland. (dpa)